<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<meta http-equiv="X-UA-Compatible" content="IE=9"/>
<meta name="generator" content="Doxygen 1.8.5"/>
<title>Faiss: /data/users/hoss/faiss/Index.h Source File</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript" src="dynsections.js"></script>
<link href="search/search.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="search/search.js"></script>
<script type="text/javascript">
  $(document).ready(function() { searchBox.OnSelectItem(0); });
</script>
<link href="doxygen.css" rel="stylesheet" type="text/css" />
</head>
<body>
<div id="top"><!-- do not remove this div, it is closed by doxygen! -->
<div id="titlearea">
<table cellspacing="0" cellpadding="0">
 <tbody>
 <tr style="height: 56px;">
  <td style="padding-left: 0.5em;">
   <div id="projectname">Faiss
   </div>
  </td>
 </tr>
 </tbody>
</table>
</div>
<!-- end header part -->
<!-- Generated by Doxygen 1.8.5 -->
<script type="text/javascript">
var searchBox = new SearchBox("searchBox", "search",false,'Search');
</script>
  <div id="navrow1" class="tabs">
    <ul class="tablist">
      <li><a href="index.html"><span>Main&#160;Page</span></a></li>
      <li><a href="namespaces.html"><span>Namespaces</span></a></li>
      <li><a href="annotated.html"><span>Classes</span></a></li>
      <li class="current"><a href="files.html"><span>Files</span></a></li>
      <li>
        <div id="MSearchBox" class="MSearchBoxInactive">
        <span class="left">
          <img id="MSearchSelect" src="search/mag_sel.png"
               onmouseover="return searchBox.OnSearchSelectShow()"
               onmouseout="return searchBox.OnSearchSelectHide()"
               alt=""/>
          <input type="text" id="MSearchField" value="Search" accesskey="S"
               onfocus="searchBox.OnSearchFieldFocus(true)" 
               onblur="searchBox.OnSearchFieldFocus(false)" 
               onkeyup="searchBox.OnSearchFieldChange(event)"/>
          </span><span class="right">
            <a id="MSearchClose" href="javascript:searchBox.CloseResultsWindow()"><img id="MSearchCloseImg" border="0" src="search/close.png" alt=""/></a>
          </span>
        </div>
      </li>
    </ul>
  </div>
  <div id="navrow2" class="tabs2">
    <ul class="tablist">
      <li><a href="files.html"><span>File&#160;List</span></a></li>
    </ul>
  </div>
</div><!-- top -->
<!-- window showing the filter options -->
<div id="MSearchSelectWindow"
     onmouseover="return searchBox.OnSearchSelectShow()"
     onmouseout="return searchBox.OnSearchSelectHide()"
     onkeydown="return searchBox.OnSearchSelectKey(event)">
<a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(0)"><span class="SelectionMark">&#160;</span>All</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(1)"><span class="SelectionMark">&#160;</span>Classes</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(2)"><span class="SelectionMark">&#160;</span>Namespaces</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(3)"><span class="SelectionMark">&#160;</span>Functions</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(4)"><span class="SelectionMark">&#160;</span>Variables</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(5)"><span class="SelectionMark">&#160;</span>Typedefs</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(6)"><span class="SelectionMark">&#160;</span>Enumerations</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(7)"><span class="SelectionMark">&#160;</span>Enumerator</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(8)"><span class="SelectionMark">&#160;</span>Friends</a></div>

<!-- iframe showing the search results (closed by default) -->
<div id="MSearchResultsWindow">
<iframe src="javascript:void(0)" frameborder="0" 
        name="MSearchResults" id="MSearchResults">
</iframe>
</div>

<div class="header">
  <div class="headertitle">
<div class="title">/data/users/hoss/faiss/Index.h</div>  </div>
</div><!--header-->
<div class="contents">
<div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno">    1</span>&#160;<span class="comment">/**</span></div>
<div class="line"><a name="l00002"></a><span class="lineno">    2</span>&#160;<span class="comment"> * Copyright (c) Facebook, Inc. and its affiliates.</span></div>
<div class="line"><a name="l00003"></a><span class="lineno">    3</span>&#160;<span class="comment"> *</span></div>
<div class="line"><a name="l00004"></a><span class="lineno">    4</span>&#160;<span class="comment"> * This source code is licensed under the MIT license found in the</span></div>
<div class="line"><a name="l00005"></a><span class="lineno">    5</span>&#160;<span class="comment"> * LICENSE file in the root directory of this source tree.</span></div>
<div class="line"><a name="l00006"></a><span class="lineno">    6</span>&#160;<span class="comment"> */</span></div>
<div class="line"><a name="l00007"></a><span class="lineno">    7</span>&#160;</div>
<div class="line"><a name="l00008"></a><span class="lineno">    8</span>&#160;<span class="comment">// -*- c++ -*-</span></div>
<div class="line"><a name="l00009"></a><span class="lineno">    9</span>&#160;</div>
<div class="line"><a name="l00010"></a><span class="lineno">   10</span>&#160;<span class="preprocessor">#ifndef FAISS_INDEX_H</span></div>
<div class="line"><a name="l00011"></a><span class="lineno">   11</span>&#160;<span class="preprocessor"></span><span class="preprocessor">#define FAISS_INDEX_H</span></div>
<div class="line"><a name="l00012"></a><span class="lineno">   12</span>&#160;<span class="preprocessor"></span></div>
<div class="line"><a name="l00013"></a><span class="lineno">   13</span>&#160;</div>
<div class="line"><a name="l00014"></a><span class="lineno">   14</span>&#160;<span class="preprocessor">#include &lt;cstdio&gt;</span></div>
<div class="line"><a name="l00015"></a><span class="lineno">   15</span>&#160;<span class="preprocessor">#include &lt;typeinfo&gt;</span></div>
<div class="line"><a name="l00016"></a><span class="lineno">   16</span>&#160;<span class="preprocessor">#include &lt;string&gt;</span></div>
<div class="line"><a name="l00017"></a><span class="lineno">   17</span>&#160;<span class="preprocessor">#include &lt;sstream&gt;</span></div>
<div class="line"><a name="l00018"></a><span class="lineno">   18</span>&#160;</div>
<div class="line"><a name="l00019"></a><span class="lineno">   19</span>&#160;<span class="preprocessor">#define FAISS_VERSION_MAJOR 1</span></div>
<div class="line"><a name="l00020"></a><span class="lineno">   20</span>&#160;<span class="preprocessor"></span><span class="preprocessor">#define FAISS_VERSION_MINOR 5</span></div>
<div class="line"><a name="l00021"></a><span class="lineno">   21</span>&#160;<span class="preprocessor"></span><span class="preprocessor">#define FAISS_VERSION_PATCH 2</span></div>
<div class="line"><a name="l00022"></a><span class="lineno">   22</span>&#160;<span class="preprocessor"></span><span class="comment"></span></div>
<div class="line"><a name="l00023"></a><span class="lineno">   23</span>&#160;<span class="comment">/**</span></div>
<div class="line"><a name="l00024"></a><span class="lineno">   24</span>&#160;<span class="comment"> * @namespace faiss</span></div>
<div class="line"><a name="l00025"></a><span class="lineno">   25</span>&#160;<span class="comment"> *</span></div>
<div class="line"><a name="l00026"></a><span class="lineno">   26</span>&#160;<span class="comment"> * Throughout the library, vectors are provided as float * pointers.</span></div>
<div class="line"><a name="l00027"></a><span class="lineno">   27</span>&#160;<span class="comment"> * Most algorithms can be optimized when several vectors are processed</span></div>
<div class="line"><a name="l00028"></a><span class="lineno">   28</span>&#160;<span class="comment"> * (added/searched) together in a batch. In this case, they are passed</span></div>
<div class="line"><a name="l00029"></a><span class="lineno">   29</span>&#160;<span class="comment"> * in as a matrix. When n vectors of size d are provided as float * x,</span></div>
<div class="line"><a name="l00030"></a><span class="lineno">   30</span>&#160;<span class="comment"> * component j of vector i is</span></div>
<div class="line"><a name="l00031"></a><span class="lineno">   31</span>&#160;<span class="comment"> *</span></div>
<div class="line"><a name="l00032"></a><span class="lineno">   32</span>&#160;<span class="comment"> *   x[ i * d + j ]</span></div>
<div class="line"><a name="l00033"></a><span class="lineno">   33</span>&#160;<span class="comment"> *</span></div>
<div class="line"><a name="l00034"></a><span class="lineno">   34</span>&#160;<span class="comment"> * where 0 &lt;= i &lt; n and 0 &lt;= j &lt; d. In other words, matrices are</span></div>
<div class="line"><a name="l00035"></a><span class="lineno">   35</span>&#160;<span class="comment"> * always compact. When specifying the size of the matrix, we call it</span></div>
<div class="line"><a name="l00036"></a><span class="lineno">   36</span>&#160;<span class="comment"> * an n*d matrix, which implies a row-major storage.</span></div>
<div class="line"><a name="l00037"></a><span class="lineno">   37</span>&#160;<span class="comment"> */</span></div>
<div class="line"><a name="l00038"></a><span class="lineno">   38</span>&#160;</div>
<div class="line"><a name="l00039"></a><span class="lineno">   39</span>&#160;</div>
<div class="line"><a name="l00040"></a><span class="lineno">   40</span>&#160;<span class="keyword">namespace </span>faiss {</div>
<div class="line"><a name="l00041"></a><span class="lineno">   41</span>&#160;</div>
<div class="line"><a name="l00042"></a><span class="lineno">   42</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00043"></a><span class="lineno">   43</span>&#160;<span class="comment">/// Some algorithms support both an inner product version and a L2 search version.</span></div>
<div class="line"><a name="l00044"></a><span class="lineno"><a class="line" href="namespacefaiss.html#afd12191c638da74760ff397cf319752c">   44</a></span>&#160;<span class="comment"></span><span class="keyword">enum</span> <a class="code" href="namespacefaiss.html#afd12191c638da74760ff397cf319752c">MetricType</a> {</div>
<div class="line"><a name="l00045"></a><span class="lineno">   45</span>&#160;    METRIC_INNER_PRODUCT = 0,</div>
<div class="line"><a name="l00046"></a><span class="lineno">   46</span>&#160;    METRIC_L2 = 1,</div>
<div class="line"><a name="l00047"></a><span class="lineno">   47</span>&#160;};</div>
<div class="line"><a name="l00048"></a><span class="lineno">   48</span>&#160;</div>
<div class="line"><a name="l00049"></a><span class="lineno">   49</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00050"></a><span class="lineno">   50</span>&#160;<span class="comment">/// Forward declarations see AuxIndexStructures.h</span></div>
<div class="line"><a name="l00051"></a><span class="lineno">   51</span>&#160;<span class="comment"></span><span class="keyword">struct </span>IDSelector;</div>
<div class="line"><a name="l00052"></a><span class="lineno">   52</span>&#160;<span class="keyword">struct </span>RangeSearchResult;</div>
<div class="line"><a name="l00053"></a><span class="lineno">   53</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00054"></a><span class="lineno">   54</span>&#160;<span class="comment">/** Abstract structure for an index</span></div>
<div class="line"><a name="l00055"></a><span class="lineno">   55</span>&#160;<span class="comment"> *</span></div>
<div class="line"><a name="l00056"></a><span class="lineno">   56</span>&#160;<span class="comment"> * Supports adding vertices and searching them.</span></div>
<div class="line"><a name="l00057"></a><span class="lineno">   57</span>&#160;<span class="comment"> *</span></div>
<div class="line"><a name="l00058"></a><span class="lineno">   58</span>&#160;<span class="comment"> * Currently only asymmetric queries are supported:</span></div>
<div class="line"><a name="l00059"></a><span class="lineno">   59</span>&#160;<span class="comment"> * database-to-database queries are not implemented.</span></div>
<div class="line"><a name="l00060"></a><span class="lineno">   60</span>&#160;<span class="comment"> */</span></div>
<div class="line"><a name="l00061"></a><span class="lineno"><a class="line" href="structfaiss_1_1Index.html">   61</a></span>&#160;<span class="keyword">struct </span><a class="code" href="structfaiss_1_1Index.html">Index</a> {</div>
<div class="line"><a name="l00062"></a><span class="lineno"><a class="line" href="structfaiss_1_1Index.html#ad3f0d3071f987baabbdd3da4500c87ea">   62</a></span>&#160;    <span class="keyword">using</span> <a class="code" href="structfaiss_1_1Index.html#ad3f0d3071f987baabbdd3da4500c87ea">idx_t</a> = long;    <span class="comment">///&lt; all indices are this type</span></div>
<div class="line"><a name="l00063"></a><span class="lineno">   63</span>&#160;<span class="comment"></span>    <span class="keyword">using</span> component_t = float;</div>
<div class="line"><a name="l00064"></a><span class="lineno">   64</span>&#160;    <span class="keyword">using</span> distance_t = float;</div>
<div class="line"><a name="l00065"></a><span class="lineno">   65</span>&#160;</div>
<div class="line"><a name="l00066"></a><span class="lineno"><a class="line" href="structfaiss_1_1Index.html#a2a002388d2c081c2dbab8508dcefe73d">   66</a></span>&#160;    <span class="keywordtype">int</span> <a class="code" href="structfaiss_1_1Index.html#a2a002388d2c081c2dbab8508dcefe73d">d</a>;                 <span class="comment">///&lt; vector dimension</span></div>
<div class="line"><a name="l00067"></a><span class="lineno"><a class="line" href="structfaiss_1_1Index.html#a6970683faa021b7a6f1a0865c0d4eccd">   67</a></span>&#160;<span class="comment"></span>    <a class="code" href="structfaiss_1_1Index.html#ad3f0d3071f987baabbdd3da4500c87ea">idx_t</a> <a class="code" href="structfaiss_1_1Index.html#a6970683faa021b7a6f1a0865c0d4eccd">ntotal</a>;          <span class="comment">///&lt; total nb of indexed vectors</span></div>
<div class="line"><a name="l00068"></a><span class="lineno"><a class="line" href="structfaiss_1_1Index.html#a5590d847c5c2b958affd2a05e58a6f23">   68</a></span>&#160;<span class="comment"></span>    <span class="keywordtype">bool</span> <a class="code" href="structfaiss_1_1Index.html#a5590d847c5c2b958affd2a05e58a6f23">verbose</a>;          <span class="comment">///&lt; verbosity level</span></div>
<div class="line"><a name="l00069"></a><span class="lineno">   69</span>&#160;<span class="comment"></span><span class="comment"></span></div>
<div class="line"><a name="l00070"></a><span class="lineno">   70</span>&#160;<span class="comment">    /// set if the Index does not require training, or if training is done already</span></div>
<div class="line"><a name="l00071"></a><span class="lineno"><a class="line" href="structfaiss_1_1Index.html#a6e92732617c4dbe364e7678dd8773a7f">   71</a></span>&#160;<span class="comment"></span>    <span class="keywordtype">bool</span> <a class="code" href="structfaiss_1_1Index.html#a6e92732617c4dbe364e7678dd8773a7f">is_trained</a>;</div>
<div class="line"><a name="l00072"></a><span class="lineno">   72</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00073"></a><span class="lineno">   73</span>&#160;<span class="comment">    /// type of metric this index uses for search</span></div>
<div class="line"><a name="l00074"></a><span class="lineno"><a class="line" href="structfaiss_1_1Index.html#a8e18f641854b2bde83ecff0a2f9a6f4e">   74</a></span>&#160;<span class="comment"></span>    <a class="code" href="namespacefaiss.html#afd12191c638da74760ff397cf319752c">MetricType</a> <a class="code" href="structfaiss_1_1Index.html#a8e18f641854b2bde83ecff0a2f9a6f4e">metric_type</a>;</div>
<div class="line"><a name="l00075"></a><span class="lineno">   75</span>&#160;</div>
<div class="line"><a name="l00076"></a><span class="lineno">   76</span>&#160;    <span class="keyword">explicit</span> <a class="code" href="structfaiss_1_1Index.html">Index</a> (<a class="code" href="structfaiss_1_1Index.html#ad3f0d3071f987baabbdd3da4500c87ea">idx_t</a> <a class="code" href="structfaiss_1_1Index.html#a2a002388d2c081c2dbab8508dcefe73d">d</a> = 0, <a class="code" href="namespacefaiss.html#afd12191c638da74760ff397cf319752c">MetricType</a> metric = METRIC_L2):</div>
<div class="line"><a name="l00077"></a><span class="lineno">   77</span>&#160;                    <a class="code" href="structfaiss_1_1Index.html#a2a002388d2c081c2dbab8508dcefe73d">d</a>(<a class="code" href="structfaiss_1_1Index.html#a2a002388d2c081c2dbab8508dcefe73d">d</a>),</div>
<div class="line"><a name="l00078"></a><span class="lineno">   78</span>&#160;                    <a class="code" href="structfaiss_1_1Index.html#a6970683faa021b7a6f1a0865c0d4eccd">ntotal</a>(0),</div>
<div class="line"><a name="l00079"></a><span class="lineno">   79</span>&#160;                    <a class="code" href="structfaiss_1_1Index.html#a5590d847c5c2b958affd2a05e58a6f23">verbose</a>(false),</div>
<div class="line"><a name="l00080"></a><span class="lineno">   80</span>&#160;                    <a class="code" href="structfaiss_1_1Index.html#a6e92732617c4dbe364e7678dd8773a7f">is_trained</a>(true),</div>
<div class="line"><a name="l00081"></a><span class="lineno">   81</span>&#160;                    <a class="code" href="structfaiss_1_1Index.html#a8e18f641854b2bde83ecff0a2f9a6f4e">metric_type</a> (metric) {}</div>
<div class="line"><a name="l00082"></a><span class="lineno">   82</span>&#160;</div>
<div class="line"><a name="l00083"></a><span class="lineno">   83</span>&#160;    <span class="keyword">virtual</span> ~<a class="code" href="structfaiss_1_1Index.html">Index</a> ();</div>
<div class="line"><a name="l00084"></a><span class="lineno">   84</span>&#160;</div>
<div class="line"><a name="l00085"></a><span class="lineno">   85</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00086"></a><span class="lineno">   86</span>&#160;<span class="comment">    /** Perform training on a representative set of vectors</span></div>
<div class="line"><a name="l00087"></a><span class="lineno">   87</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00088"></a><span class="lineno">   88</span>&#160;<span class="comment">     * @param n      nb of training vectors</span></div>
<div class="line"><a name="l00089"></a><span class="lineno">   89</span>&#160;<span class="comment">     * @param x      training vecors, size n * d</span></div>
<div class="line"><a name="l00090"></a><span class="lineno">   90</span>&#160;<span class="comment">     */</span></div>
<div class="line"><a name="l00091"></a><span class="lineno">   91</span>&#160;    <span class="keyword">virtual</span> <span class="keywordtype">void</span> <a class="code" href="structfaiss_1_1Index.html#abf601502bdbfa02b9d7bcd7b3671b71d">train</a>(idx_t n, <span class="keyword">const</span> <span class="keywordtype">float</span>* x);</div>
<div class="line"><a name="l00092"></a><span class="lineno">   92</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00093"></a><span class="lineno">   93</span>&#160;<span class="comment">    /** Add n vectors of dimension d to the index.</span></div>
<div class="line"><a name="l00094"></a><span class="lineno">   94</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00095"></a><span class="lineno">   95</span>&#160;<span class="comment">     * Vectors are implicitly assigned labels ntotal .. ntotal + n - 1</span></div>
<div class="line"><a name="l00096"></a><span class="lineno">   96</span>&#160;<span class="comment">     * This function slices the input vectors in chuncks smaller than</span></div>
<div class="line"><a name="l00097"></a><span class="lineno">   97</span>&#160;<span class="comment">     * blocksize_add and calls add_core.</span></div>
<div class="line"><a name="l00098"></a><span class="lineno">   98</span>&#160;<span class="comment">     * @param x      input matrix, size n * d</span></div>
<div class="line"><a name="l00099"></a><span class="lineno">   99</span>&#160;<span class="comment">     */</span></div>
<div class="line"><a name="l00100"></a><span class="lineno">  100</span>&#160;    <span class="keyword">virtual</span> <span class="keywordtype">void</span> <a class="code" href="structfaiss_1_1Index.html#a1b5e9ac70adbce0897dd6c8276ad96f2">add</a> (idx_t n, <span class="keyword">const</span> <span class="keywordtype">float</span> *x) = 0;</div>
<div class="line"><a name="l00101"></a><span class="lineno">  101</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00102"></a><span class="lineno">  102</span>&#160;<span class="comment">    /** Same as add, but stores xids instead of sequential ids.</span></div>
<div class="line"><a name="l00103"></a><span class="lineno">  103</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00104"></a><span class="lineno">  104</span>&#160;<span class="comment">     * The default implementation fails with an assertion, as it is</span></div>
<div class="line"><a name="l00105"></a><span class="lineno">  105</span>&#160;<span class="comment">     * not supported by all indexes.</span></div>
<div class="line"><a name="l00106"></a><span class="lineno">  106</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00107"></a><span class="lineno">  107</span>&#160;<span class="comment">     * @param xids if non-null, ids to store for the vectors (size n)</span></div>
<div class="line"><a name="l00108"></a><span class="lineno">  108</span>&#160;<span class="comment">     */</span></div>
<div class="line"><a name="l00109"></a><span class="lineno">  109</span>&#160;    <span class="keyword">virtual</span> <span class="keywordtype">void</span> <a class="code" href="structfaiss_1_1Index.html#aa6931dfe054b33b02c842ff75f7a0c7f">add_with_ids</a> (idx_t n, <span class="keyword">const</span> <span class="keywordtype">float</span> * x, <span class="keyword">const</span> <span class="keywordtype">long</span> *xids);</div>
<div class="line"><a name="l00110"></a><span class="lineno">  110</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00111"></a><span class="lineno">  111</span>&#160;<span class="comment">    /** query n vectors of dimension d to the index.</span></div>
<div class="line"><a name="l00112"></a><span class="lineno">  112</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00113"></a><span class="lineno">  113</span>&#160;<span class="comment">     * return at most k vectors. If there are not enough results for a</span></div>
<div class="line"><a name="l00114"></a><span class="lineno">  114</span>&#160;<span class="comment">     * query, the result array is padded with -1s.</span></div>
<div class="line"><a name="l00115"></a><span class="lineno">  115</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00116"></a><span class="lineno">  116</span>&#160;<span class="comment">     * @param x           input vectors to search, size n * d</span></div>
<div class="line"><a name="l00117"></a><span class="lineno">  117</span>&#160;<span class="comment">     * @param labels      output labels of the NNs, size n*k</span></div>
<div class="line"><a name="l00118"></a><span class="lineno">  118</span>&#160;<span class="comment">     * @param distances   output pairwise distances, size n*k</span></div>
<div class="line"><a name="l00119"></a><span class="lineno">  119</span>&#160;<span class="comment">     */</span></div>
<div class="line"><a name="l00120"></a><span class="lineno">  120</span>&#160;    <span class="keyword">virtual</span> <span class="keywordtype">void</span> <a class="code" href="structfaiss_1_1Index.html#aced51b1ebc33c47ab3ae15ea906559a7">search</a> (idx_t n, <span class="keyword">const</span> <span class="keywordtype">float</span> *x, idx_t k,</div>
<div class="line"><a name="l00121"></a><span class="lineno">  121</span>&#160;                         <span class="keywordtype">float</span> *distances, idx_t *labels) <span class="keyword">const</span> = 0;</div>
<div class="line"><a name="l00122"></a><span class="lineno">  122</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00123"></a><span class="lineno">  123</span>&#160;<span class="comment">    /** query n vectors of dimension d to the index.</span></div>
<div class="line"><a name="l00124"></a><span class="lineno">  124</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00125"></a><span class="lineno">  125</span>&#160;<span class="comment">     * return all vectors with distance &lt; radius. Note that many</span></div>
<div class="line"><a name="l00126"></a><span class="lineno">  126</span>&#160;<span class="comment">     * indexes do not implement the range_search (only the k-NN search</span></div>
<div class="line"><a name="l00127"></a><span class="lineno">  127</span>&#160;<span class="comment">     * is mandatory).</span></div>
<div class="line"><a name="l00128"></a><span class="lineno">  128</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00129"></a><span class="lineno">  129</span>&#160;<span class="comment">     * @param x           input vectors to search, size n * d</span></div>
<div class="line"><a name="l00130"></a><span class="lineno">  130</span>&#160;<span class="comment">     * @param radius      search radius</span></div>
<div class="line"><a name="l00131"></a><span class="lineno">  131</span>&#160;<span class="comment">     * @param result      result table</span></div>
<div class="line"><a name="l00132"></a><span class="lineno">  132</span>&#160;<span class="comment">     */</span></div>
<div class="line"><a name="l00133"></a><span class="lineno">  133</span>&#160;    <span class="keyword">virtual</span> <span class="keywordtype">void</span> <a class="code" href="structfaiss_1_1Index.html#a236897832a58dbb205e2d662c1929fb1">range_search</a> (idx_t n, <span class="keyword">const</span> <span class="keywordtype">float</span> *x, <span class="keywordtype">float</span> radius,</div>
<div class="line"><a name="l00134"></a><span class="lineno">  134</span>&#160;                               <a class="code" href="structfaiss_1_1RangeSearchResult.html">RangeSearchResult</a> *result) <span class="keyword">const</span>;</div>
<div class="line"><a name="l00135"></a><span class="lineno">  135</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00136"></a><span class="lineno">  136</span>&#160;<span class="comment">    /** return the indexes of the k vectors closest to the query x.</span></div>
<div class="line"><a name="l00137"></a><span class="lineno">  137</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00138"></a><span class="lineno">  138</span>&#160;<span class="comment">     * This function is identical as search but only return labels of neighbors.</span></div>
<div class="line"><a name="l00139"></a><span class="lineno">  139</span>&#160;<span class="comment">     * @param x           input vectors to search, size n * d</span></div>
<div class="line"><a name="l00140"></a><span class="lineno">  140</span>&#160;<span class="comment">     * @param labels      output labels of the NNs, size n*k</span></div>
<div class="line"><a name="l00141"></a><span class="lineno">  141</span>&#160;<span class="comment">     */</span></div>
<div class="line"><a name="l00142"></a><span class="lineno">  142</span>&#160;    <span class="keywordtype">void</span> <a class="code" href="structfaiss_1_1Index.html#a8bc5d8d1cd0dd7b34b3c98a9f76b4a9c">assign</a> (idx_t n, <span class="keyword">const</span> <span class="keywordtype">float</span> * x, idx_t * labels, idx_t k = 1);</div>
<div class="line"><a name="l00143"></a><span class="lineno">  143</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00144"></a><span class="lineno">  144</span>&#160;<span class="comment">    /// removes all elements from the database.</span></div>
<div class="line"><a name="l00145"></a><span class="lineno">  145</span>&#160;<span class="comment"></span>    <span class="keyword">virtual</span> <span class="keywordtype">void</span> <a class="code" href="structfaiss_1_1Index.html#a849361f5f0ab0aba8d419c86f2594191">reset</a>() = 0;</div>
<div class="line"><a name="l00146"></a><span class="lineno">  146</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00147"></a><span class="lineno">  147</span>&#160;<span class="comment">    /** removes IDs from the index. Not supported by all indexes</span></div>
<div class="line"><a name="l00148"></a><span class="lineno">  148</span>&#160;<span class="comment">     */</span></div>
<div class="line"><a name="l00149"></a><span class="lineno">  149</span>&#160;    <span class="keyword">virtual</span> <span class="keywordtype">long</span> <a class="code" href="structfaiss_1_1Index.html#af8bf7bd97aeed8ad5fc48b242379a68a">remove_ids</a> (<span class="keyword">const</span> <a class="code" href="structfaiss_1_1IDSelector.html">IDSelector</a> &amp; sel);</div>
<div class="line"><a name="l00150"></a><span class="lineno">  150</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00151"></a><span class="lineno">  151</span>&#160;<span class="comment">    /** Reconstruct a stored vector (or an approximation if lossy coding)</span></div>
<div class="line"><a name="l00152"></a><span class="lineno">  152</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00153"></a><span class="lineno">  153</span>&#160;<span class="comment">     * this function may not be defined for some indexes</span></div>
<div class="line"><a name="l00154"></a><span class="lineno">  154</span>&#160;<span class="comment">     * @param key         id of the vector to reconstruct</span></div>
<div class="line"><a name="l00155"></a><span class="lineno">  155</span>&#160;<span class="comment">     * @param recons      reconstucted vector (size d)</span></div>
<div class="line"><a name="l00156"></a><span class="lineno">  156</span>&#160;<span class="comment">     */</span></div>
<div class="line"><a name="l00157"></a><span class="lineno">  157</span>&#160;    <span class="keyword">virtual</span> <span class="keywordtype">void</span> <a class="code" href="structfaiss_1_1Index.html#aaef6f4132b1f390121ebb11058baf190">reconstruct</a> (idx_t key, <span class="keywordtype">float</span> * recons) <span class="keyword">const</span>;</div>
<div class="line"><a name="l00158"></a><span class="lineno">  158</span>&#160;</div>
<div class="line"><a name="l00159"></a><span class="lineno">  159</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00160"></a><span class="lineno">  160</span>&#160;<span class="comment">    /** Reconstruct vectors i0 to i0 + ni - 1</span></div>
<div class="line"><a name="l00161"></a><span class="lineno">  161</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00162"></a><span class="lineno">  162</span>&#160;<span class="comment">     * this function may not be defined for some indexes</span></div>
<div class="line"><a name="l00163"></a><span class="lineno">  163</span>&#160;<span class="comment">     * @param recons      reconstucted vector (size ni * d)</span></div>
<div class="line"><a name="l00164"></a><span class="lineno">  164</span>&#160;<span class="comment">     */</span></div>
<div class="line"><a name="l00165"></a><span class="lineno">  165</span>&#160;    <span class="keyword">virtual</span> <span class="keywordtype">void</span> <a class="code" href="structfaiss_1_1Index.html#a1936604fffe16b0ef2a3879305950738">reconstruct_n</a> (idx_t i0, idx_t ni, <span class="keywordtype">float</span> *recons) <span class="keyword">const</span>;</div>
<div class="line"><a name="l00166"></a><span class="lineno">  166</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00167"></a><span class="lineno">  167</span>&#160;<span class="comment">    /** Similar to search, but also reconstructs the stored vectors (or an</span></div>
<div class="line"><a name="l00168"></a><span class="lineno">  168</span>&#160;<span class="comment">     * approximation in the case of lossy coding) for the search results.</span></div>
<div class="line"><a name="l00169"></a><span class="lineno">  169</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00170"></a><span class="lineno">  170</span>&#160;<span class="comment">     * If there are not enough results for a query, the resulting arrays</span></div>
<div class="line"><a name="l00171"></a><span class="lineno">  171</span>&#160;<span class="comment">     * is padded with -1s.</span></div>
<div class="line"><a name="l00172"></a><span class="lineno">  172</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00173"></a><span class="lineno">  173</span>&#160;<span class="comment">     * @param recons      reconstructed vectors size (n, k, d)</span></div>
<div class="line"><a name="l00174"></a><span class="lineno">  174</span>&#160;<span class="comment">     **/</span></div>
<div class="line"><a name="l00175"></a><span class="lineno">  175</span>&#160;    <span class="keyword">virtual</span> <span class="keywordtype">void</span> <a class="code" href="structfaiss_1_1Index.html#aa5b4e63e1064f9bf9c75625d114b353f">search_and_reconstruct</a> (idx_t n, <span class="keyword">const</span> <span class="keywordtype">float</span> *x, idx_t k,</div>
<div class="line"><a name="l00176"></a><span class="lineno">  176</span>&#160;                                         <span class="keywordtype">float</span> *distances, idx_t *labels,</div>
<div class="line"><a name="l00177"></a><span class="lineno">  177</span>&#160;                                         <span class="keywordtype">float</span> *recons) <span class="keyword">const</span>;</div>
<div class="line"><a name="l00178"></a><span class="lineno">  178</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00179"></a><span class="lineno">  179</span>&#160;<span class="comment">    /** Computes a residual vector after indexing encoding.</span></div>
<div class="line"><a name="l00180"></a><span class="lineno">  180</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00181"></a><span class="lineno">  181</span>&#160;<span class="comment">     * The residual vector is the difference between a vector and the</span></div>
<div class="line"><a name="l00182"></a><span class="lineno">  182</span>&#160;<span class="comment">     * reconstruction that can be decoded from its representation in</span></div>
<div class="line"><a name="l00183"></a><span class="lineno">  183</span>&#160;<span class="comment">     * the index. The residual can be used for multiple-stage indexing</span></div>
<div class="line"><a name="l00184"></a><span class="lineno">  184</span>&#160;<span class="comment">     * methods, like IndexIVF&#39;s methods.</span></div>
<div class="line"><a name="l00185"></a><span class="lineno">  185</span>&#160;<span class="comment">     *</span></div>
<div class="line"><a name="l00186"></a><span class="lineno">  186</span>&#160;<span class="comment">     * @param x           input vector, size d</span></div>
<div class="line"><a name="l00187"></a><span class="lineno">  187</span>&#160;<span class="comment">     * @param residual    output residual vector, size d</span></div>
<div class="line"><a name="l00188"></a><span class="lineno">  188</span>&#160;<span class="comment">     * @param key         encoded index, as returned by search and assign</span></div>
<div class="line"><a name="l00189"></a><span class="lineno">  189</span>&#160;<span class="comment">     */</span></div>
<div class="line"><a name="l00190"></a><span class="lineno">  190</span>&#160;    <span class="keywordtype">void</span> <a class="code" href="structfaiss_1_1Index.html#aaae77608bbda70b1098897e9167a82f9">compute_residual</a> (<span class="keyword">const</span> <span class="keywordtype">float</span> * x, <span class="keywordtype">float</span> * residual, idx_t key) <span class="keyword">const</span>;</div>
<div class="line"><a name="l00191"></a><span class="lineno">  191</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00192"></a><span class="lineno">  192</span>&#160;<span class="comment">    /** Display the actual class name and some more info */</span></div>
<div class="line"><a name="l00193"></a><span class="lineno">  193</span>&#160;    <span class="keywordtype">void</span> <a class="code" href="structfaiss_1_1Index.html#a373c30e3d87d1d4e616f450d87152b1a">display</a> () <span class="keyword">const</span>;</div>
<div class="line"><a name="l00194"></a><span class="lineno">  194</span>&#160;</div>
<div class="line"><a name="l00195"></a><span class="lineno">  195</span>&#160;</div>
<div class="line"><a name="l00196"></a><span class="lineno">  196</span>&#160;</div>
<div class="line"><a name="l00197"></a><span class="lineno">  197</span>&#160;};</div>
<div class="line"><a name="l00198"></a><span class="lineno">  198</span>&#160;</div>
<div class="line"><a name="l00199"></a><span class="lineno">  199</span>&#160;}</div>
<div class="line"><a name="l00200"></a><span class="lineno">  200</span>&#160;</div>
<div class="line"><a name="l00201"></a><span class="lineno">  201</span>&#160;</div>
<div class="line"><a name="l00202"></a><span class="lineno">  202</span>&#160;<span class="preprocessor">#endif</span></div>
<div class="ttc" id="structfaiss_1_1Index_html_a849361f5f0ab0aba8d419c86f2594191"><div class="ttname"><a href="structfaiss_1_1Index.html#a849361f5f0ab0aba8d419c86f2594191">faiss::Index::reset</a></div><div class="ttdeci">virtual void reset()=0</div><div class="ttdoc">removes all elements from the database. </div></div>
<div class="ttc" id="structfaiss_1_1Index_html_aa5b4e63e1064f9bf9c75625d114b353f"><div class="ttname"><a href="structfaiss_1_1Index.html#aa5b4e63e1064f9bf9c75625d114b353f">faiss::Index::search_and_reconstruct</a></div><div class="ttdeci">virtual void search_and_reconstruct(idx_t n, const float *x, idx_t k, float *distances, idx_t *labels, float *recons) const </div><div class="ttdef"><b>Definition:</b> <a href="Index_8cpp_source.html#l00066">Index.cpp:66</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_a8bc5d8d1cd0dd7b34b3c98a9f76b4a9c"><div class="ttname"><a href="structfaiss_1_1Index.html#a8bc5d8d1cd0dd7b34b3c98a9f76b4a9c">faiss::Index::assign</a></div><div class="ttdeci">void assign(idx_t n, const float *x, idx_t *labels, idx_t k=1)</div><div class="ttdef"><b>Definition:</b> <a href="Index_8cpp_source.html#l00034">Index.cpp:34</a></div></div>
<div class="ttc" id="structfaiss_1_1IDSelector_html"><div class="ttname"><a href="structfaiss_1_1IDSelector.html">faiss::IDSelector</a></div><div class="ttdef"><b>Definition:</b> <a href="AuxIndexStructures_8h_source.html#l00054">AuxIndexStructures.h:54</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_abf601502bdbfa02b9d7bcd7b3671b71d"><div class="ttname"><a href="structfaiss_1_1Index.html#abf601502bdbfa02b9d7bcd7b3671b71d">faiss::Index::train</a></div><div class="ttdeci">virtual void train(idx_t n, const float *x)</div><div class="ttdef"><b>Definition:</b> <a href="Index_8cpp_source.html#l00023">Index.cpp:23</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_aa6931dfe054b33b02c842ff75f7a0c7f"><div class="ttname"><a href="structfaiss_1_1Index.html#aa6931dfe054b33b02c842ff75f7a0c7f">faiss::Index::add_with_ids</a></div><div class="ttdeci">virtual void add_with_ids(idx_t n, const float *x, const long *xids)</div><div class="ttdef"><b>Definition:</b> <a href="Index_8cpp_source.html#l00041">Index.cpp:41</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_a2a002388d2c081c2dbab8508dcefe73d"><div class="ttname"><a href="structfaiss_1_1Index.html#a2a002388d2c081c2dbab8508dcefe73d">faiss::Index::d</a></div><div class="ttdeci">int d</div><div class="ttdoc">vector dimension </div><div class="ttdef"><b>Definition:</b> <a href="Index_8h_source.html#l00066">Index.h:66</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_ad3f0d3071f987baabbdd3da4500c87ea"><div class="ttname"><a href="structfaiss_1_1Index.html#ad3f0d3071f987baabbdd3da4500c87ea">faiss::Index::idx_t</a></div><div class="ttdeci">long idx_t</div><div class="ttdoc">all indices are this type </div><div class="ttdef"><b>Definition:</b> <a href="Index_8h_source.html#l00062">Index.h:62</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_a1936604fffe16b0ef2a3879305950738"><div class="ttname"><a href="structfaiss_1_1Index.html#a1936604fffe16b0ef2a3879305950738">faiss::Index::reconstruct_n</a></div><div class="ttdeci">virtual void reconstruct_n(idx_t i0, idx_t ni, float *recons) const </div><div class="ttdef"><b>Definition:</b> <a href="Index_8cpp_source.html#l00059">Index.cpp:59</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_a1b5e9ac70adbce0897dd6c8276ad96f2"><div class="ttname"><a href="structfaiss_1_1Index.html#a1b5e9ac70adbce0897dd6c8276ad96f2">faiss::Index::add</a></div><div class="ttdeci">virtual void add(idx_t n, const float *x)=0</div></div>
<div class="ttc" id="structfaiss_1_1Index_html_a6970683faa021b7a6f1a0865c0d4eccd"><div class="ttname"><a href="structfaiss_1_1Index.html#a6970683faa021b7a6f1a0865c0d4eccd">faiss::Index::ntotal</a></div><div class="ttdeci">idx_t ntotal</div><div class="ttdoc">total nb of indexed vectors </div><div class="ttdef"><b>Definition:</b> <a href="Index_8h_source.html#l00067">Index.h:67</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_a5590d847c5c2b958affd2a05e58a6f23"><div class="ttname"><a href="structfaiss_1_1Index.html#a5590d847c5c2b958affd2a05e58a6f23">faiss::Index::verbose</a></div><div class="ttdeci">bool verbose</div><div class="ttdoc">verbosity level </div><div class="ttdef"><b>Definition:</b> <a href="Index_8h_source.html#l00068">Index.h:68</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_af8bf7bd97aeed8ad5fc48b242379a68a"><div class="ttname"><a href="structfaiss_1_1Index.html#af8bf7bd97aeed8ad5fc48b242379a68a">faiss::Index::remove_ids</a></div><div class="ttdeci">virtual long remove_ids(const IDSelector &amp;sel)</div><div class="ttdef"><b>Definition:</b> <a href="Index_8cpp_source.html#l00048">Index.cpp:48</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_aced51b1ebc33c47ab3ae15ea906559a7"><div class="ttname"><a href="structfaiss_1_1Index.html#aced51b1ebc33c47ab3ae15ea906559a7">faiss::Index::search</a></div><div class="ttdeci">virtual void search(idx_t n, const float *x, idx_t k, float *distances, idx_t *labels) const =0</div></div>
<div class="ttc" id="structfaiss_1_1RangeSearchResult_html"><div class="ttname"><a href="structfaiss_1_1RangeSearchResult.html">faiss::RangeSearchResult</a></div><div class="ttdef"><b>Definition:</b> <a href="AuxIndexStructures_8h_source.html#l00031">AuxIndexStructures.h:31</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_a373c30e3d87d1d4e616f450d87152b1a"><div class="ttname"><a href="structfaiss_1_1Index.html#a373c30e3d87d1d4e616f450d87152b1a">faiss::Index::display</a></div><div class="ttdeci">void display() const </div><div class="ttdef"><b>Definition:</b> <a href="Index_8cpp_source.html#l00094">Index.cpp:94</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_a8e18f641854b2bde83ecff0a2f9a6f4e"><div class="ttname"><a href="structfaiss_1_1Index.html#a8e18f641854b2bde83ecff0a2f9a6f4e">faiss::Index::metric_type</a></div><div class="ttdeci">MetricType metric_type</div><div class="ttdoc">type of metric this index uses for search </div><div class="ttdef"><b>Definition:</b> <a href="Index_8h_source.html#l00074">Index.h:74</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html"><div class="ttname"><a href="structfaiss_1_1Index.html">faiss::Index</a></div><div class="ttdef"><b>Definition:</b> <a href="Index_8h_source.html#l00061">Index.h:61</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_a236897832a58dbb205e2d662c1929fb1"><div class="ttname"><a href="structfaiss_1_1Index.html#a236897832a58dbb205e2d662c1929fb1">faiss::Index::range_search</a></div><div class="ttdeci">virtual void range_search(idx_t n, const float *x, float radius, RangeSearchResult *result) const </div><div class="ttdef"><b>Definition:</b> <a href="Index_8cpp_source.html#l00028">Index.cpp:28</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_a6e92732617c4dbe364e7678dd8773a7f"><div class="ttname"><a href="structfaiss_1_1Index.html#a6e92732617c4dbe364e7678dd8773a7f">faiss::Index::is_trained</a></div><div class="ttdeci">bool is_trained</div><div class="ttdoc">set if the Index does not require training, or if training is done already </div><div class="ttdef"><b>Definition:</b> <a href="Index_8h_source.html#l00071">Index.h:71</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_aaae77608bbda70b1098897e9167a82f9"><div class="ttname"><a href="structfaiss_1_1Index.html#aaae77608bbda70b1098897e9167a82f9">faiss::Index::compute_residual</a></div><div class="ttdeci">void compute_residual(const float *x, float *residual, idx_t key) const </div><div class="ttdef"><b>Definition:</b> <a href="Index_8cpp_source.html#l00086">Index.cpp:86</a></div></div>
<div class="ttc" id="structfaiss_1_1Index_html_aaef6f4132b1f390121ebb11058baf190"><div class="ttname"><a href="structfaiss_1_1Index.html#aaef6f4132b1f390121ebb11058baf190">faiss::Index::reconstruct</a></div><div class="ttdeci">virtual void reconstruct(idx_t key, float *recons) const </div><div class="ttdef"><b>Definition:</b> <a href="Index_8cpp_source.html#l00054">Index.cpp:54</a></div></div>
<div class="ttc" id="namespacefaiss_html_afd12191c638da74760ff397cf319752c"><div class="ttname"><a href="namespacefaiss.html#afd12191c638da74760ff397cf319752c">faiss::MetricType</a></div><div class="ttdeci">MetricType</div><div class="ttdoc">Some algorithms support both an inner product version and a L2 search version. </div><div class="ttdef"><b>Definition:</b> <a href="Index_8h_source.html#l00044">Index.h:44</a></div></div>
</div><!-- fragment --></div><!-- contents -->
<!-- start footer part -->
<hr class="footer"/><address class="footer"><small>
Generated by &#160;<a href="http://www.doxygen.org/index.html">
<img class="footer" src="doxygen.png" alt="doxygen"/>
</a> 1.8.5
</small></address>
</body>
</html>
